And by the way …

Q: My boyfriend and I both love to say “by the way” when we want to change the subject in a relevant way. However, we are curious about the etymology of this phrase. Can you enlighten us?

A: This is a nifty question and the answer requires an etymological journey that takes us back to the earliest days of English and the language’s even earlier Germanic roots.

The word “way” has been used to mean a road or path since Old English, and it’s descended from Germanic roots that go back to prehistory.

When “by the way” (or “by way”) first appeared in the 900s, its meaning was literal, according to the Oxford English Dictionary: “along or near the road by which one travels; by the road-side.”

Around the year 1000, the phrase was first used to mean “while going along, in the course of one’s walk or journey.”

This is how Shakespeare used the expression in A Midsummer Night’s Dream (1590): “Lets follow him, and by the way let us recount our dreames.”

In the mid-16th century, “by the way” developed another meaning, a figurative one used in conversation and discourse: “incidentally, in passing, as a side-topic.”

Shakespeare used this one as well, in The Merry Wives of Windsor (1598): “Shee is pretty, and honest, and gentle, and one that is your friend, I can tell you that by the way.”

Now we arrive at the modern-day meaning, which the OED says is “used parenthetically to apologize for introducing a new topic, a casual remark, or the like.” This usage was introduced in 1614.

Here’s an example, from Edward Burt’s Letters From a Gentleman in the North of Scotland (circa 1730): “By the Way, altho’ the Weather was not warm, he was without Shoes, Stockings, or Breeches.”

And here’s one from Charles Dickens’s Sketches by Boz (1836): “This, by the way, was another bit of diplomacy.”

In case you’re wondering, a similar phrase, “by the by” (or “by the bye”), came along from a different route.

The first “by” in the expression is a preposition, but the second is actually an obscure noun, one that once meant “a secondary or subsidiary object, course, or undertaking; a side issue; something of minor importance.”

That obscure noun lives on in “by the by,” which was introduced in the 1600s and which means, the OED says, “by a side way, on a side issue; as a matter of secondary or subsidiary importance, incidentally, casually, in passing.”

George Eliot used the phrase this way in her novel Middlemarch (1872): “All these matters were by the by.”

In the 1700s “by the by” acquired its modern meaning, which is more or less a parenthetical “by the way.”

Jonathan Swift is credited with the first use in print, writing as the pseudonymous Isaac Bickerstaff (1708): “I hear my wife’s voice, (which by the by, is pretty distinguishable).”